Thanks, Robb. Great reply. I'll check out the links you posted. I'm playing NL25-NL50 6max, so is it really profitable to fold AJ from MP?

My UTG range consist of AA-22, ATs+, KQo+.
My MP range includes UTG range and ATo+ and maybe some suited connectors depending on the table. Do you have some advice on starting hands from UTG and MP?